With the wide proliferation of cordless and cellular telephones, it is increasingly common to have a phone in close proximity while listening to the radio in a car or watching television at home. There are currently over 66 million cellular telephone users in the United States, and this number is increasing rapidly. Cell phone users carry these devices wherever they go, particularly since newer services cover much a broader area, including the entire country in a growing number of situations.
It would be advantageous, if not profitable, for advertisers and other information providers to interact with telephone users, particularly if it the interaction results in the sale of products or services in a given area. Ironically, even with the growing number of portable phones, it is difficult for consumers to respond to offers or receive more information from advertisers. One source of the difficulty is the large number of digits that must entered to contact the advertiser and identify the type of information desired.
Radio advertisers, in particular, now reach a greater number of individuals in close proximity to a telephone due to the widespread use of mobile phones. Nevertheless, if the driver or passenger in an automobile must dial a seven-digit number followed by several other pushbutton entries to obtain certain information, many will either forget the number to call or lose interest. Even with automated voice-prompted menu selections, the caller might need to remain on the line longer than they wish to.
U.S. Pat. No. 5,703,795, which is incorporated herein by reference, discloses the derivation of station (S), date (D), time (T) and response (#) data to correlate a user's response to a particular piece of broadcast information (SDT). In each case, however, specified hardware is required for storing SDT# at a receiver site, and for communicating the data via the Internet or a point-of-sale (POS) system to a central location, where it is compared to broadcast station logs to convey an appropriate reply to the user. If an SDT-type protocol could take advantage of existing telecommunications devices, the resulting system might be more easily implemented since even fewer changes would be required to the existing infrastructure.